Switzerland as a federal state

The rise of Switzerland as a federal state began on 12 September 1848, with the creation of a federal constitution in response to a 27-day civil war, the Sonderbundskrieg. The constitution, which was heavily influenced by the United States Constitution and the ideas of the French Revolution, was modified several times during the following decades and wholly replaced in 1999. The 1848 constitution represented the first time, other than when the short-lived Helvetic Republic had been imposed, that the Swiss had a central government instead of being simply a collection of autonomous cantons bound by treaties.

In 1847, the period of Swiss history known as Restoration ended with a war between the conservative Roman Catholic and the liberal Protestant cantons . The conflict between the Catholic and Protestant cantons had existed since the Reformation; in the 19th century the Protestant population had a majority. The Sonderbund was concluded after the Radical Party had taken power in Switzerland and had, thanks to the Protestant majority of cantons, taken measures against the Catholic Church such as the closure of monasteries and convents in Aargau in 1841. When Lucerne, in retaliation, recalled the Jesuits the same year, groups of armed radicals invaded the canton. The invasion caused a revolt, mostly because rural cantons were strongholds of ultramontanism.

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